A selectively powered layered network and a method thereof

ABSTRACT

A layered network ( 10; 11; 12 ) to provide offload of data in a communication processor ( 100; 110; 120 ). The layered network ( 10; 11; 12 ) includes a first set (S 1 ) of network elements at a first layer (L 1 ) and a second set (S 2 ) of one or more network elements at a second layer (L 2 ). The network elements of the first set (S 1 ) are configured for processing incoming data and the network elements of the second set (S 2 ) of one or more network elements at the second layer (L 2 ) are configured to process intermediate data received from the first set (S 1 ) of network elements. The network elements of a particular subset (S i1 ) of the network elements of the first set (S i1 ) of network elements are connected to only a particular network element (E i2 ) of the second set (S 2 ) to transfer the incoming data processed by the network elements of the particular subset (S i1 ) to the particular network element (E i2 ) of the second set (S 2 ). The layered network ( 10; 11; 12 ) further includes a powering controller ( 25 ) configured to, during offload of the data, put a particular network element (E i2 ) of the second set (S 2 ) at the second layer (L 2 ) in an on state only if at least a particular network element (E i1 ) of the particular subset (S 1 ) of the network elements of the first set (S 1 ) at the first layer (L 1 ) is in an on state and at least one of the network elements of the first set (S 1 ) is in an off state. The powering controller ( 25 ) is configured to discriminate between chains of network elements formed by at least network elements of the first set (S 1 ) and network elements of the second set (S 2 ) and to have a chain in an on state if a first network element of the chain at a highest layer hierarchy is in an on state.

FIELD OF THE INVENTION

This invention relates to a layered network and to a method ofcontrolling a layered network in a communication processor. Theinvention further relates to a layered offload network and to a layereddebug network, and to a communication processor including any of saidlayered offload network and/or layered debug network. Additionally theinvention relates to a wired or wireless communication system includingany of said layered offload/debug networks or the communicationprocessor.

BACKGROUND OF THE INVENTION

In order to increase the performance of communication processors,hardware accelerators such as offload networks may be typically used.Offload networks are capable of processing data that otherwise would beprocessed in a processing unit in the communication processor therebyreducing the performance of the processing unit. Offload networks havetypically a layered architecture, i.e. a series of network elements maybe instantiated between different modules in the communication processor(e.g. IP blocks communicating with the processing unit in thecommunication processor) to create an offload network that can operateat high speed. The layered architecture may be a modular layeredarchitecture which provides a considerable flexibility of re-using theoffload layered network for different applications. Thus, the layeredoffload network may be used in general purpose communication processorsor may be customized for a particular application. The network elementsof the series of network elements in successive layers collect tracemessages from remote sources and provide synchronization, arbitrationand storage of the trace messages. The series of network elements formsa chain of network elements to aggregate data offloaded from theprocessing unit in the communication processor. Once that data isoffloaded from the processing unit in the communication processor, theoffloaded data is received from a first set of network elements at afirst layer of the layered offload network. Once the offloaded data isprocessed by the network elements at the first layer, the processedoffloaded data is received by a second set of network elements at asecond layer and so on until a final network element at a last layer ofthe layered offload network aggregates all processed offloaded datathrough the layers of the layered offload network and provides an outputof the layered offload network. A number of network elements at thefirst layer may be greater than a number of network elements at thesecond layer and the number of network elements at the second layer maybe greater than a number of network elements at the third layer until asingle network element at the last layer is reached. The networkelements of the layered offload network may also provide conversion ofthe offloaded processed data into various bus formats to allow theoutput of the layered offload network to access an external memory. Thelayered offload network may thus provide an alternative path for thecommunication processor in which the data is not sent directly from theprocessing unit of the communication processor to the external memorybut it is offloaded from the layered offload network and sent to theexternal memory via the output of the layered offload network.

One of the problems associated with existing layered offload networks isthat the increase of performance of the communication processor comes atthe expenses of substantial extra power consumption. In fact, in orderto offload data from the processing unit in the communication processor,the layered offload network needs to be fully powered-on to ensureoffloading of the data and thereby releasing the processing unit fromthe burden of processing a larger amount of data. In fact the networkelements of existing layered offload networks are typically connected toa master power down which turns on or turns off all network elements inthe layered offload network. If the layered offload network is designedto work at high clock speeds as it may be usually required, the powerconsumption of the fully turned on layered offload network duringoffloading of the data may exceed the maximum power consumption allowedin the particular application for which the layered offload network maybe customized.

SUMMARY OF THE INVENTION

The present invention provides a layered network that provides offloadof data in a communication processor, a communication processorincluding the layered network, a wired or wireless communication systemincluding said layered network or said communication processor. Thepresent invention further provides a method of controlling a layerednetwork in a communication processor and a computer program productincluding instructions to cause a computer system to perform saidmethod.

Specific embodiments of the invention are set forth in the dependentclaims.

These and other aspects of the invention will be apparent from andelucidated with reference to the embodiments described hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

Further details, aspects and embodiments of the invention will bedescribed, by way of example only, with reference to the drawings.

FIG. 1 schematically shows an example of an embodiment of a layerednetwork embedded in a communication processor,

FIG. 2 schematically shows a further example of an embodiment of alayered network embedded in a communication processor,

FIG. 3 schematically shows another example of an embodiment of a layerednetwork embedded in a communication processor,

FIG. 4 schematically shows an example of an adaptive power controllerused in the layered network of FIG. 3 and an example of input codedframe,

FIG. 5 schematically shows an example of a power budget algorithm unitused in the adaptive power controller shown in FIG. 4, and

FIG. 6 schematically shows a flow chart of a method of controlling alayered network in a communication processor.

Elements in the figures are illustrated for simplicity and clarity andhave not necessarily been drawn to scale. In the Figures, elements whichcorrespond to elements already described may have the same referencenumerals.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 schematically shows an example of an embodiment of a layerednetwork 10 embedded in a communication processor 100. The layerednetwork 10 may be a layered offload network 10 that provides offload ofdata in the communication processor 100 during a normal mode ofoperation of the communication processor 100, i.e. during a functionalmode of operation of the communication processor 100. The layerednetwork 10 may be a layered debug network to perform diagnostic ortesting operations in the communication processor 100 when thecommunication processor 100 works in a test mode of operation, i.e. whenthe communication processor 100 or constituent parts of thecommunication processor 100 are tested for debugging the communicationprocessor 100. We will refer in the rest of this document and if nototherwise specified, to the layered network 10 as to the layered offloadnetwork 10. The communication processor 100 may be a general purposecommunication processor 100 which may support a variety of communicationsystems. The communication system supported by the communicationprocessor 100 may be a wired or wireless communication system in whichfor example audio, video or other data is processed. The communicationsystem supported by the communication processor 100 may be for examplean Ethernet system. The layered offload network 10 shown in FIG. 1 isembedded in the communication processor 100. The layered offload network10 may be integrated in the communication processor 100 in the samechip, for example in order to obtain a system on chip (SoC) basedcommunication processor 100. Alternatively the layered offload network10 may be external to the communication processor 100 and integrated ina different chip than a chip wherein the communication processor 100 isintegrated. The communication processor 100 may include one or more coreprocessors 102 to process data, a central bus 140 (e.g. a central fabricwith some processing power capabilities) and one or more IP units, IP₁to IP_(N), to perform various functions. For example the one or more IPunits, IP₁ to IP_(N), may handle communication protocols such asEthernet protocol and/or perform controlling functions or memory accessfunctions. The communication processor 100 may share a memory unit 150with the layered offload network 10. The memory unit 150 may be embeddedin the communication processor 100, or as shown in FIG. 1, the memoryunit 150 may be external to the communication processor 100. The memoryunit 150 may be used to store data processed by the communicationprocessor 100 via the central bus 140 or processed by the layeredoffload network 10. Each of the one or more core processors 102 of thecommunication processor 100 may have a separate cache memory (not shownin FIG. 1). A change occurring in the shared memory unit 150 may bereplicated into each one of the separate cache memories such thatchanges in the shared memory unit 150 may be propagated through thecommunication processor 100 in a timely fashion. Cache coherency ensuresthat the memory unit 150 may be shared between the one or more coreprocessors 102 efficiently. In other words the central bus 140 processescoherent data, i.e. data which needs to be consistent through each oneof the separate cache memories of the shared memory unit 150. On thecontrary data offloaded in the communication processor 100 to thelayered offload network 10 and processed in the layered offload network10 is non-coherent data, i.e. data that does not need to be copied fromthe memory unit 150 into local cache memories.

The layered offload network 10 includes a first set S₁ of networkelements at a first layer L1 of the layered offload network 10. Thenetwork elements of the first set S₁ are configured to process incomingdata. In the example of FIG. 1 the data offloaded in the communicationprocessor 100 is offloaded via the one or more IP units, IP₁ to IP_(N),to corresponding network elements E_(i0) of the layered offload network10 interfacing the one or more IP units, IP₁ to IP_(N), with the networkelements of the first set S₁, E₁₁ to E_(N1). One or more inputinterfacing layers may be arranged between the first layer L1 and theone or more IP units, IP₁ to IP_(N). In FIG. 1 only one inputinterfacing layer Lin is shown. The network elements E_(i0) at the inputinterfacing layer Lin offload and process the data in the communicationprocessor 100 coming from the corresponding one or more IP units, IP₁ toIP_(N). The offloaded data processed by network elements E_(i0) at theinput interfacing layer Lin is received as incoming data by the networkelements, E₁₁ to E_(N1), at the first layer L1. The layered offloadnetwork 10 further includes a second set S₂ of network elements at thesecond layer L2, i.e. the network elements E₁₂, E_(i2), etc. The networkelements of the second set S₂ at the second layer L2 are configured toprocess intermediate data received from the first set S₁ of networkelements, E₁₁ to E_(N1). The network elements, E₁₁ to E_(N1), of thefirst set S₁ are hardware blocks capable to collect incoming data, i.e.data offloaded from the one or more IP units, IP₁ to IP_(N), andprocessed in the one or more input interfacing layers. Similarly, thenetwork elements of the second set S₂ are hardware blocks capable tocollect intermediate data coming from the network elements, E₁₁ toE_(N1), of the first set S₁. The network elements of the first set S₁and of the second set S₂ provide synchronization, arbitration and/orstorage of the incoming data and the intermediate data. The networkelements of the first set S₁ and of the second set S₂ may provideconversion of data into various bus formats to access, via one or moreoutput interfacing layers subsequent to the second layer L2, the memoryunit 150. One or more output interfacing layers may be arranged betweenthe second layer L2 and a layered offload network output Outn. In FIG. 1only one output interfacing layer Lout is shown. The layered offloadnetwork 10 includes a powering controller 25 to have in an on or offstate the network elements of the second set S₂ at the second layer L2.The powering controller 25 is configured to have in an on state, duringoffload of data, a particular network element E_(i2) of the second setS₂ at the second layer L2 only if at least a particular network elementE_(i1) of a particular subset S_(i1) of network elements of the firstset S₁ at the first layer L1 is in an on state and one of the networkelements of the first set S₁ is in an off state. The network elements ofthe particular subset S_(i1) at the first layer L1 are all connected toonly the particular network element E_(i2) of the second set S₂ at thesecond layer L2. The powered off network element of the first set S₁ maybelong or may not belong to the particular subset S_(i1). Since at leasta network element of the first set S₁ is in an off state while theparticular network element E_(i2) of the second set S₂ and at least aparticular network element E_(i1) of a particular subset S_(i1) are inan on state, power consumption of the layered offload network 10 and ofthe communication processor 100 wherein the layered offload network 10may be embedded is at least reduced compared to a situation in which allnetwork elements in the layered offload network 10 are turned on. Morethan one network element of the first set S₁ may be powered off whilethe particular network element E_(i2) of the second set S₂ is in an onstate. In this latter case the power consumption of the layered offloadnetwork 10 and of the communication processor 100 may be furtherreduced. Existing layered offload networks have typically a master powercontroller unit that indiscriminately turns-on all network elements inthe existing layered offload networks during offload of data in acommunication processor and indiscriminately turns-off all networkelements in the existing layered offload networks when offload of datais not performed. The proposed invention instead includes a poweringcontroller 25 which discriminates between the network elements in thelayered offload network 10 and puts in an on state a particular networkelement E_(i2) of the second set S₂ at the second layer only if at leastone of the network elements of the first set S₁ connected to particularnetwork element E_(i2) is turned on. In this way a chain of turned onnetwork elements is established which offloads the data in thecommunication processor 100 and transfers the processed offloaded datadown in the layer hierarchy of the layered offload network 10, i.e. fromthe input interfacing layer Lin through the first layer L1 and thesecond layer L2 to the output interfacing layer Lout. In a similar way achain of powered-off network elements through the layer hierarchy of thelayered offload network 10 may be established from the input interfacinglayer Lin through the first layer L1 and the second layer L2 to theoutput interfacing layer Lout. In other words, the powering controller25 may be configured to discriminate between chains of network elementsformed by at least network elements of the first set S₁ and networkelements of the second set S₂ and to have a chain in an on state if thefirst network element of the chain is in an on state. The first networkelement of the chain is the network element at the highest level of thechain, i.e. at the first layer L1 in the example of the layered offloadnetwork 10 with only the first layer L1 and the second layer L2. Ifthere are more than two layers of network elements as shown in FIG. 1,the first network element at the highest level of the chain is a networkelement at the input interfacing layer Lin. In this latter case thechain includes all powered on network elements at the input interfacinglayer Lin and at the output interfacing layer Lout which are connectedin series along the chain to the network elements at the first layer L1and at the second layer L2.

The layered offload network 10 shown in FIG. 1 further includes anadaptive power controller 50. The adaptive power controller 50 isconfigured to keep in an on state the particular network element E_(i2)of the second set S₂ at the second layer L2 and the at least aparticular network element E_(i1) of the particular subset S_(i1) ofnetwork elements at the first layer L1 if a combined power consumptionof the particular network element E_(i2) of the second set S₂ at thesecond layer L2 and the at least a particular network element E_(i1) ofthe particular subset S_(i1) is within a maximum power budget of thelayered offload network 10. In other words, the particular networkelement E_(i2) at the second layer L2 and the particular network elementE_(i1) at the first layer L1 are kept in an on state if the combinedpower consumption of the particular network element E_(i2) of the secondset S₂ at the second layer L2 and of the at least a particular networkelement E_(i1) of the particular subset S_(i1) of network elements atthe first layer L1 summed to the remainder power consumption of thelayered offload network 10 is lower than an allowed maximum power budgetfor the particular application in which the layered offload network 10is used. In this way the total power consumption of the layered offloadnetwork 10 may be adapted to the requirements of the application inwhich the layered offload network 10 is used.

The adaptive power controller 50 may be further configured to turn-offsaid chain formed by the particular network element E_(i2) of the secondset S₂ at the second layer L2 and the at least a particular networkelement E_(i1) of the particular subset S_(i1), if the combined powerconsumption of the particular network element E_(i2) of the second setS₂ at the second layer L2 and of the at least a particular networkelement E_(i1) of the particular subset S_(i1) of network elements atthe first layer L1 exceeds the maximum power budget of the layeredoffload network 10 and if the at least a particular network elementE_(i1) of said particular subset S_(i1) and the particular networkelement E_(i2) of the second set S₂ were not already kept in an on stateby the adaptive power controller 50 but turned on during aninitialisation of the layered offload network 10. In this way onlychains of network elements initialized and turned on once during astart-up of the layered offload network 10 may be turned off if thepower consumption of said chains summed to the remainder powerconsumption of the layered offload network 10 is higher than the maximumpower budget allowed by the application. On the contrary chains ofnetwork elements that were previously kept in an on state by theadaptive power controller 50 because their power consumption was notexceeding the maximum power budget allowed in the layered offloadnetwork 10, may not be turned off by the adaptive power controller 50.By keeping in an on state already approved chains of network elements toprocess and transfer the offloaded data and by de-activating chains thatincrease the power consumption of the layered offload network 10 abovethe maximum allowed power budget in the layered offload network 10, theadaptive power controller 50 optimizes the power consumption in thelayered offload network 10 and thus in the communication processor 100wherein the layered offload network 10 may be embedded.

As said, the layered offload network 10 may have one or a plurality ofinput interfacing layers interfacing the network elements, E₁₁ toE_(N1), at the first layer L1, to the one or more IP units, IP₁ toIP_(N). The layered offload network 10 may also have one or a pluralityof further output interfacing layers interfacing the network elements,E₁₂, E_(i2), etc., at the second layer L2 to an output of layeredoffload network 10.

Alternatively in another embodiment shown in FIG. 2, the networkelements, E₁₁ to E_(N1), of the first set S₁ a the first layer L1 mayhave inputs to directly receive and process data offloaded in thecommunication processor 110 via the one or more IP units, IP₁ to IP_(N).As shown for example in FIG. 2 the layered offload network 11 has aplurality of sets, S₃ to S_(N), of network elements at a correspondingplurality of further layers, L3 to LN, subsequent to the second layerL2. A third set of network elements S₃ is at a correspondent third layerL3; a fourth set S₄ of network elements would be at a correspondentfourth layer L4, and so on. The layered offload network 11 shown in FIG.2 further includes a last network element E_(1N) at the last layer LN ofthe corresponding plurality of further layers. The last network elementE_(1N) is configured to receive the data processed in the networkelements at layers preceding the last layer LN and to provide an outputsignal of the layered offload network 11 to the memory unit 150 to storethe data processed in the layered offload network 11 in the memory unit150. By having a plurality of sets, S₃ to S_(N), at a correspondingplurality of further layers, L3 to LN, subsequent to the second layerL2, the layered offload network 11 shown in FIG. 2 may have an increasedspeed and provide an increased buffering of data compared to a layeredoffload network with less layers, thereby further decreasing the burdenin the central bus 140 or in the one or more core processors 102 causedby processing large amount of non-coherent data.

In another alternative embodiment not shown in the Figures, the secondset S₂ of one or more network elements, E₁₂, E_(i2), etc., may have onlyone network element providing the layered network output Outn. Thelayered network output Outn provides output data to the memory unit 150.The memory unit 150 may be configured to store the output data processedin the layered offload network 11. In this embodiment, the second layerL2 corresponds to the last layer LN of the layered offload network 11and the only one network element corresponds to the last network elementE_(1N) of the layered offload network 11.

What has been so far described for the layered offload network 10 ofFIG. 1, i.e. for a layered offload network with two sets S₁ and S₂ ofnetwork elements at two corresponding layers L1 and L2, can be extendedto the multi-sets multi-layers layered offload network illustrated inFIG. 2 in which the first set S₁ of network elements, E₁₁ to E_(N1), atthe first layer L1, processes incoming data directly received andoffloaded from the one or more IP units, IP₁ to IP_(N). In the layeredoffload network 11 of FIG. 2, the powering controller 25 is arrangedbetween the first set S₁ and the second set S₂ as in FIG. 1. In additionto the power controller 25, power controllers 27 and 29 are arrangedbetween the second set S₂ and the third set S₃, and between the thirdset S₃ and the last set S_(N) respectively. The power controllers 27 and29 are configured, similarly to the power controller 25, to have on,during the offload of data, a particular network element of theplurality of sets, S₃ to S_(N), at a particular layer of thecorresponding plurality of further layers, L3 to LN, only if at least aparticular network element of a particular subset of network elements ofa further set at a layer immediately preceding the particular layer isin an on state while one of the network elements at any of thecorresponding plurality of further layers preceding the particular layeris in an off state. The network elements of the particular subset of thefurther set of network elements are connected to the particular networkelement of the plurality of set, S₃ to S_(N), at the particular layer.Since chains of network elements having more than only two networkelements may be powered off while at least a chain of network elementshaving more than only two network elements is turned on, the overallpower consumption of the layered offload network 11, and of thecorrespondent communication processor 110 wherein the layered offloadnetwork 11 may be embedded, may be further reduced.

In the layered offload network 11 of FIG. 2 the adaptive powercontroller 51, similarly to the power controller 50 shown in FIG. 1, isconfigured to keep in an on state a chain of network elements throughthe layers L1 to LN if a power consumption of the chain is within amaximum power budget of the layered offload network 11. Said chain ofnetwork elements includes the last network element E_(1N) at the lastlayer LN (or the only one network element of the second layer L2 in theembodiment above mentioned) and a series of network elements at layerspreceding the last layer LN connected in series with the last networkelement E_(1N).

Similarly to the example of FIG. 1, the chain of network elements ofFIG. 2 may be turned off by the adaptive power controller 51 if a powerconsumption of the chain exceeds the maximum power budget of the layeredoffload network 11 and if all network elements of the chain were notalready kept in an on state by the adaptive power controller 51 butturned on during an initialisation of the layered offload network 11.The adaptive power controller 51 ensures thus that a chain of networkelements, that was previously approved and kept on by the adaptive powercontroller 51 because the power consumption of the chain was fallingwithin the maximum power budget of the layered offload network 11, isnot accidentally turned off at a later stage if another additional chainof network elements is not anymore approved by the adaptive powercontroller 51.

FIG. 3 shows a practical implementation of the powering controllers 25,27 and 29 described in FIG. 2. The powering controllers 26, 28 and 30shown in FIG. 2 include OR gates. For example the powering controller 26includes an OR gate that has inputs receiving an on or an off statecontrol signal from correspondent outputs of the network elements E_(i1)of the particular subset S_(i1) of network elements. The OR gate has anoutput to put on the particular network element E_(i2) of the second setS₂ at the second layer L2 if any of the inputs of the OR gate receivesan on state control signal which indicates an on state from the at leasta particular network element E_(i1) of said particular subset S_(i1) ofnetwork elements at the first layer L1. It should be noted that thenetwork elements E_(i1) of the particular subset S_(i1) are connected inseries to the particular network element E_(i2) of the second set S₂ atthe second layer L2 to transfer the intermediate data from the firstlayer L1 to the particular network elements E_(i2) of the second layerL2. These connections that refer to the data transfer have not beenshown in FIG. 3 to simplify the drawing. In FIG. 3 only power controlconnections are shown between network elements at different layers. Thepower controllers 28 have OR gates with inputs receiving an on or an offstate control signal from correspondent outputs of network elements ofother particular subsets of network elements at the second layer L2.These latter OR gates have outputs to switch or keep in an on statefurther particular network elements E_(i3), E_(j3) of a third set S₃ ofnetwork elements at the third layer L3 if any of the inputs of theselatter OR gates receives an on state control signal which indicates anon state from at least a further particular network element of saidother particular subsets of network elements at the second layer L2. Thenetwork elements of said other particular subsets of network elements atthe second layer L2 are connected to the further particular networkelements E_(i3), E_(j3) to transfer the processed data from the secondlayer L2 to the further particular network elements E₃, E_(j3) at thethird layer L3. The powering controller 30 is arranged at an interfacebetween the last network element E_(1N) at the last layer LN and othernetwork elements at another layer immediately preceding the last layerLN. The powering controller 30 includes only one OR gate because onlyone output may be required to control the unique last element E_(1N) atthe last layer LN.

The powering controllers 26, 28 and 30 shown in FIG. 3 which may be apractical implementation of the powering controllers 25, 27 and 29 shownin FIG. 2, may ensure that at least a chain of turned-on networkelements from the first layer L1 to the last layer LN is establishedduring the offload of data in the communication processor 120.

FIG. 4 shows an example of an implementation of the adaptive powercontroller 51 shown in FIG. 1 to FIG. 3. The adaptive power controller51 includes a decoder to decode a coded frame 70 containing anidentification code, ID1 to IDN, (every element in the layered network11 or 12 adds its identification code) and an on or off state active bitAB for each network element of the layered network 11 or 12 that hasprocessed the coded frame 70. An example of coded frame 70 processed bythe network elements through the layers of the layered network 11 or 12is illustrated in FIG. 4. The layered networks 11 or 12 may be initiallypowered by the one or more IP units, IP₁ to IP_(N), shown through FIG. 1to FIG. 3. The one or more IP units, IP₁ to IP_(N), may send the codedframe 70 to power up the network elements at the first layer L1 of thelayered network 11 or 12 of FIG. 2 or FIG. 3. A chain of networkelements including at least a first network element of the first set S₁and a second network element of the second set S₂ connected to the firstnetwork element is not activated until the coded frame 70 reaches thelast network element E_(1N) of the layered network 11 or 12. Along apath connecting the first network element E_(i1) at the first layer L1to the last network element E_(1N) at the last layer LN, the coded frame70 is processed and modified by each network element along the path. Thecoded frame 70 includes a transaction code TCODE to establish whether ornot the coded frame 70 is associated with an offload functionality ofthe layered network 11 or 12. The coded frame 70 may be associated to adifferent functionality than the offload functionality of the layerednetwork 11 or 12. For example the layered network 11 or 12 so fardescribed as a layered offload network 11 or 12 may be working not onlyto offload data in the communication processor 100, 110 or 120 but alsoas a layered debug network to perform diagnostic or testing operationsin the communication processor 100, 110 or 120 during a test mode ofoperation of the communication processor 100, 110 or 120. The layereddebug network may for example be used to test the one or more IP unitsof the communication processor 100, 110 or 120 by providing, during atest mode of operation of the communication processor 100, 110 or 120,access to internal signals in the one or more IP units that wouldotherwise be not accessible during a normal mode of operation of thecommunication processor 100, 110 or 120. On the contrary, the layeredoffload network is operative in normal mode of operation because offloadof data must happen when the one or more core processors 102 in thecommunication processor 100, 110 or 120 are overloaded, therebyimproving the performance of the one or more core processors 102 duringnormal mode of operation. The coded frame 70 may thus be used toidentify whether the layered network so far described is working as alayered offload network or as layered debug network by bringing thisinformation in the transaction code TCODE. The coded frame 70 furtherincludes a coded frame identifier IFI of the coded frame 70. The codedframe identifier IFI may be used to indicate for example if the codedframe 70 is a regular traffic frame or a request frame used to power upthe first network element E_(i1) at the first layer L1. The adaptivepower controller 51 further includes a power budget table 65 that storesthe identification code, ID1 to IDN, and a corresponding powerconsumption of the all network elements in the layered network 11 or 12.The power budget table may be for example a memory programmed table bysoftware. The adaptive power controller 51 further includes a powerbudget algorithm unit 60 that receives the coded frame 70 decoded by thedecoder 55. The power budget algorithm unit 60 further receivesmeasurement data from sensors. The power budget algorithm unit 60 may beimplemented with software instructions. The power budget algorithm unit60 may calculate a current power consumption of the layered network 11or 12 from measurement data of currently active chains of networkelements. For example the sensors may detect currents or voltages ortemperatures from which a total current power consumption of the layerednetwork may be calculated. The power budget algorithm model unit 60 mayalso read and update the content of the power budget table 65 accordingfor example to the measurement data retrieved by the sensors. The powerbudget algorithm model 60 may provide an output signal to instruct ornot the offload of data via the chain of network elements that has beenmodifying the coded frame 70.

Referring to FIG. 5, the power budget algorithm unit 60 includes aconversion logic unit 72, a static power register 74, a current powerconsumption register 76, an offload delta power consumption register 78,an adder 80, a maximum power register 82, a comparator 84 and an eventqueue register 86. The conversion logic unit 72 converts the measurementdata received from the sensors into the current power consumption. Theconversion logic unit 72 calculates the current power consumption of thelayered network 11 or 12 from the measurement data retrieved by thesensors. The static power register 74 stores an estimate of the currentpower consumption if no measurement data is available from the sensors,or if no sensors are used. In fact the sensors may not be implemented inwhich case an estimate of the current power consumption is taken basedfor example on the application in which the layered network 11 or 12 isused. The static power register 74 may be pre-programmed whileacquisition of measurements data from the sensors may be dynamic. Thecurrent power consumption register 76 stores the current powerconsumption derived from the measurement data of the sensors or theestimate of the current power consumption stored in the static powerregister 74. A configuration bit 75, pre-configured by the user,determines whether the current power consumption derived from themeasurement data of the sensors or the estimate of the current powerconsumption stored in the static power register 74 is used. The offloaddelta power consumption register 78 stores a delta power consumption ofchains of network elements that have been activated in addition tocurrently active chains of network elements. The offload delta powerconsumption register 78 stores an extra power consumption of the newlyactivated chains of network elements compared to the already activatedchains of network elements. The adder 80 adds up the current powerconsumption or the estimate of the current power consumption stored inthe current power consumption register 76 to the delta power consumptionto obtain a total power consumption. The comparator 84 compares amaximum allowed power budget stored in the maximum power register 82with the total power consumption. Finally the event queue register 86writes a first identification code of the corresponding first element ofthe additional activated chain of network elements to identify, in casethe total power consumption has exceeded the maximum power budget, whichchain may be turned off by the one or more IP units, IP₁ to IP_(N), ofthe communication processor 110 or 120. In case the total powerconsumption has not exceeded the maximum power budget, the event queueregister 86 will keep in an on state the related additional activatedchains allowing the offload of data.

In the embodiments described with reference to the FIGS. 1, 2 and 3, thecommunication processor 100, 110 and 120 includes the layered network10, 11 and 12 respectively. As said, alternatively the layered network10, 11 or 12 may be external to the communication processor 100, 110 or120. Furthermore an integrated circuit may integrate the layered network10, 11 or 12 so far described or the communication processor 100, 110 or120 including or excluding the layered network 10, 11 or 12.

FIG. 6 shows a flow diagram of a method to control a layered network 10in a communication processor 100. The layered network 10 and thecommunication processor 100 have been already both described withreference to FIG. 1 and their descriptions will be not repeated herebelow. In a first step 200 of the method, incoming data is processed bythe network elements of the first set S₁. In a second step 300intermediate data is processed by the one or more network elements ofthe second set S₂. The intermediate data is received from the networkelements of the first set S₁. The method further includes: having in anon state 300 a particular network element E_(i2) of the second set S₂only if at least a particular network element E_(i1) of the particularsubset S_(i1) of network elements of the first set S₁ at the first layerL1 is in an on state.

The method to control the layered network 10, after the step 400 ofhaving on the particular network element E_(i2) of the second set S₂,may include additional steps illustrated in the flow chart of FIG. 6with dashed boxes. Acquisition 500 of a current power consumption ofcurrently activated chains of network elements is performed. The chainsof network elements at least include a network element of the first setS₁ and a network element of the second set S₂. Acquisition 600 of adelta power consumption of chains of network elements activated inaddition to the currently activated chains of network elements isadditionally performed. The method may further includes a step of adding700 the current power consumption to the delta power consumption toobtain a total power consumption and comparing 800 the total powerconsumption with a maximum power budget of the layered network 10 tokeep in an on state 900 the chains of network elements activated inaddition to current chains of network elements if the total powerconsumption is lower than the maximum power budget or to turn off 1000the chains of network elements activated in addition to the currentlyactivated chains of network elements if the total power consumption ishigher than the maximum power budget.

In one embodiment a computer program product (e.g. a software product)may include instructions that are run in a computer system to performthe steps of the method above described.

The computer system may be a personal computer system. Other embodimentsmay include different types of computer systems. Computer systems areinformation handling systems which can be designed to give independentcomputing power to one or more users. Computer systems may be found inmany forms including but not limited to mainframes, minicomputers,servers, workstations, personal computers, notepads, personal digitalassistants, electronic games, automotive and other embedded systems,cell phones and various other wireless devices. A typical computersystem includes at least one processing unit, associated memory and anumber of input/output (I/O) devices.

A computer system processes information according to a program andproduces resultant output information via I/O devices. A program is alist of instructions such as a particular application program and/or anoperating system. A computer program is typically stored internally oncomputer readable storage medium or transmitted to the computer systemvia a computer readable transmission medium. A computer processtypically includes an executing (running) program or portion of aprogram, current program values and state information, and the resourcesused by the operating system to manage the execution of the process. Aparent process may spawn other, child processes to help perform theoverall functionality of the parent process. Because the parent processspecifically spawns the child processes to perform a portion of theoverall functionality of the parent process, the functions performed bychild processes (and grandchild processes, etc.) may sometimes bedescribed as being performed by the parent process.

Also, the invention is not limited to physical devices or unitsimplemented in non-programmable hardware but can also be applied inprogrammable devices or units able to perform the desired devicefunctions by operating in accordance with suitable program code.Furthermore, the devices may be physically distributed over a number ofapparatuses, while functionally operating as a single device.

Also, devices functionally forming separate devices may be integrated ina single physical device. Also, the units and circuits may be suitablycombined in one or more semiconductor devices. For example the layerednetwork 10, 11 or 12 may be integrated in a single chip with all theremaining constituent parts of the communication processor 100, 110 and120. Alternatively the layered network 10, 11 or 12 may be integrated ina separated chip to a chip in which all the remaining constituent partsof the communication processor 100, 110 and 120 may be integrated.However, other modifications, variations and alternatives are alsopossible. The specifications and drawings are, accordingly, to beregarded in an illustrative rather than in a restrictive sense. In theclaims, any reference signs placed between parentheses shall not beconstrued as limiting the claim. The word ‘comprising’ does not excludethe presence of other elements or steps then those listed in a claim.Furthermore, Furthermore, the terms “a” or “an,” as used herein, aredefined as one or more than one. Also, the use of introductory phrasessuch as “at least one” and “one or more” in the claims should not beconstrued to imply that the introduction of another claim element by theindefinite articles “a” or “an” limits any particular claim containingsuch introduced claim element to inventions containing only one suchelement, even when the same claim includes the introductory phrases “oneor more” or “at least one” and indefinite articles such as “a” or “an.”The same holds true for the use of definite articles. Unless statedotherwise, terms such as “first” and “second” are used to arbitrarilydistinguish between the elements such terms describe. Thus, these termsare not necessarily intended to indicate temporal or otherprioritization of such elements. The mere fact that certain measures arerecited in mutually different claims does not indicate that acombination of these measures cannot be used to advantage.

1. A layered network for providing offload of data in a communication processor, the layered network comprising: a first set of network elements at a first layer, said network elements of the first set being configured for processing incoming data, a second set of one or more network elements at a second layer, said one or more network elements of the second set being configured for processing intermediate data received from the first set of network elements, network elements of a particular subset of the network elements of the first set of network elements being connected to only a particular network element of the second set for transferring the incoming data processed by the network elements of the particular subset to the particular network element of the second set, a powering controller being configured for, during offload of the data, having the particular network element of the second set at the second layer in an on state only if at least a particular network element of the particular subset of the network elements of the first set at the first layer is in an on state and at least one of the network elements of the first set is in an off state.
 2. A layered network-according to claim 1 further comprising an adaptive power controller, the adaptive power controller being configured for keeping in an on state the particular network element of the second set at the second layer and the at least a particular network element of said particular subset of network elements at the first layer if a power consumption of the particular network element of the second set and of the at least a particular network element of said particular subset is within a maximum power budget of the layered network.
 3. A layered network according to claim 2 wherein the adaptive power controller is further configured for turning off the particular network element of the second set at the second layer and the at least a particular network element of said particular subset of network elements at the first layer which are in the on state if a power consumption of the particular network element of the second set and of the at least a particular network element of said particular subset exceeds the maximum power budget of the layered network and if the at least a particular network element of said particular subset and the particular network element of the second set were not already kept in an on state by the adaptive power controller but turned on during an initialisation of the layered network.
 4. A layered network according to claim 1 wherein the network elements of the first set have inputs for directly receiving and processing data offloaded in the communication processor.
 5. A layered network according to claim 1 wherein the second set has only one network element for providing a layered network output to provide output data to a memory unit, the memory unit being configured for storing the output data processed in the layered network.
 6. A layered network according to claim 1 wherein the powering controller comprises an OR gate, wherein the OR gate has inputs for receiving a state control signal from correspondent outputs of the network elements of the particular subset and an output for having in an on state the corresponding particular network element of the second set at the second layer if any of the inputs of the OR gate receives a state control signal which indicates an on state from the at least a particular network element of said particular subset of network elements at the first layer.
 7. A layered network according to claim 6 wherein the adaptive power controller comprises: a decoder for decoding a coded frame; the coded frame comprising: an identification code for identifying network elements in a chain of network elements comprising a first network element of the first set and a second network element of the second set connected to the first network element, an on or off state active bit defining the state control signal for identifying an on or off state of the network elements in the chain, a code frame identifier for identifying the coded frame, and a transaction code for identifying the layered network, the coded frame being processed by the network elements in the last mentioned chain; a power budget table for storing the identification code and a corresponding power consumption of all the network elements in the layered network, a power budget algorithm unit for receiving the decoded coded frame, for receiving measurement data from sensors, the measurement data being representative for a current power consumption of the currently active chains of network elements, and for reading and updating the corresponding power consumption in the power budget table.
 8. A layered network according to claim 7 wherein the power budget algorithm unit comprises: a conversion logic unit for converting the measurement data received from the sensors into the current power consumption of the layered network, a static power register for holding an estimation of the current power consumption in the layered network, a current power consumption register for storing the current power consumption from the conversion logic unit or the estimation of the current power consumption from the static power register, an offload delta power consumption register for storing a delta power consumption of chains of network elements activated in addition to currently active chains of network elements of the layered network, an adder for adding the current power consumption or the estimation of the current power consumption to the delta power consumption to obtain a total power consumption, a maximum power register for storing the maximum allowed power budget in the layered network, a comparator for comparing the maximum allowed power budget with the total power consumption, an event queue register for storing a first identification code of a corresponding first network element of the additional activated chains, and for keeping in an on state the additional activated chains if the total power consumption has not exceeded the maximum allowed power budget, and for turning off the additional activated chains if the total power consumption has exceeded the maximum allowed power budget.
 9. The layered network according to claim 1 wherein the layered network is a layered offload network providing, during a normal mode of operation of the communication processor, offload of data in the communication processor.
 10. The layered network according to claim 1 wherein the layered network is a layered debug network providing, during a test mode of operation of the communication processor, diagnostic or testing operation in the communication processor.
 11. A communication processor comprising the layered network as claimed in claim
 1. 12. An integrated circuit comprising the layered network as claimed in claim
 1. 13. A wired or wireless communication system comprising the layered network according to claim
 1. 14. A wired communication system according to claim 13 wherein the wired communication system is an Ethernet communication system.
 15. A method of controlling a layered network in a communication processor, the layered network comprising: a first set of network elements at a first layer comprising a particular subset of network elements, a second set of one or more network elements at a second layer comprising a particular network element connected to only the network elements of the particular subset of network elements; the method comprising: processing incoming data by the network elements of the first set to obtain intermediate data, processing the intermediate data by the one or more network elements of the second set, having in an on state the particular network element of the second set only if at least a particular network element of the particular subset of network elements of the first set at the first layer is in an on state and one of the network elements of the first set is in an off state.
 16. The method of controlling the layered network as claimed in claim 15, the method further comprising after the having in an on state: acquiring a current power consumption of the layered network of currently activated chains of network elements, the chains comprising at least a first network element of the first set and a second network element of the second set connected to the first network element, acquiring a delta power consumption of chains of network elements activated in addition to current chains of network elements activated during the current operation of the layered network, adding the current power consumption to the delta power consumption to obtain a total power consumption, comparing the total power consumption with a maximum power budget of the layered network, keeping in an on state the chains of network elements activated in addition to current chains of network elements if the total power consumption is lower than the maximum power budget, turning off the chains of network elements activated in addition to current chains of network elements if the total power consumption is higher than the maximum power budget.
 17. A computer program product comprising instructions for causing a computer system to perform the method according to the claim
 15. 